Thursday, October 19, 2017

Early European Farmers Skipped The Baltics

In most of Europe, "Early European Farmers" genetically similar to Anatolian Neolithic farmers and modern Sardinians introduced farming. Then, their economies collapsed eventually in the Middle Neolithic during which populations were infused with hunter-gatherer ancestry, probably due to unsustainable farming practices and climate issues. Then, steppe pastoralists (mostly Indo-European) swept in resulting in major population genetic changes and a rival of societies that took on something close to their current population genetic character in the Late Neolithic/Enolithic/early Bronze Age.

But, this is not what happened in the Baltics. The Early European Farmers never arrived and their first wave of farming arrived with steppe people, according to a new ancient DNA based analysis of the question. Also, while Early European Farmers dramatically replaced local hunter-gatherer populations, Baltic Mesolithic populations had more staying power, so while they had a significant infusion of steppe ancestry into their populations, there is more continuity there between Mesolithic non-farmers and modern populations in these areas.

This could have happened in part because many Baltic hunter-gatherers were maritime fisher-gatherer populations, which are intermediate between terrestrial hunter-gatherer populations and farmers and have more staying power. It could also have happened, in part, because the crops in the Early European Farmer package were ill adapted to high latitude climates. So, the locals had more staying power while the would be incoming Neolithic migrants were at their weakest there, therefore the migration didn't happen.